1. Field of the Invention
The present invention relates to a method for forming a fine pattern of a polymer thin film, and more particularly, to a method of simply and conveniently forming a fine pattern of a polymer thin film.
2. Discussion of Related Art
An organic thin film transistor (OTFT) uses a semiconductor layer formed of an organic thin film, instead of a silicon layer, which may be classified as a low molecular OTFT such as oligothiophene, pentacene, etc., or a polymer OTFT such as polythiophene, etc., depending on the material of the organic thin film.
In order to fabricate the OTFT, a process of patterning an organic thin film is essentially needed. For this purpose, in the conventional art, a photolithography process is performed to pattern the organic thin film.
However, problems with this include that the photolithography is complicated, the polymer organic thin film may be damaged by an organic solvent included in a photoresist, and a substrate having low thermal stability must be processed at a low temperature.
For this reason, a method of printing a pattern of a polymer organic thin film through an inkjet method, a spin coating method, etc., has been proposed. When the polymer organic thin film pattern is formed by the printing method, adhesive force to a substrate is an important factor. In order to improve the adhesive force to the substrate, conventional plasma surface treatment has been performed.
However, since it is difficult for the conventional plasma surface treatment method to finely control a portion of a substrate surface to be plasma surface treated, it is very difficult to form a fine pattern of less than several micrometers and to form a polymer organic thin film at a desired position in a desired direction.